Ionic bonding
Ionic bonding is a fundamental type of chemical bonding that occurs primarily between metals and non-metals. In this process, atoms transfer electrons, resulting in the formation of charged particles known as ions. Metals, which typically have one to three electrons in their outer shell, tend to lose these electrons, becoming positively charged cations. Conversely, non-metals, which have five to seven electrons in their outer shell, gain electrons, becoming negatively charged anions. The resulting attraction between these oppositely charged ions creates a strong ionic bond.
Compounds formed through ionic bonding are called ionic compounds, characterized by their unique three-dimensional crystal lattice structure. This arrangement ensures that the overall charge of the compound is neutral, requiring a balance between cations and anions. Ionic compounds generally exhibit distinct properties, such as high melting and boiling points, and are often found in solid form. They also dissolve in water, allowing them to conduct electricity when their ionic bonds break, separating the charged particles. Understanding ionic bonding is essential for studying various chemical compounds and their behaviors in different contexts.
Ionic bonding
Ionic bonding is a type of chemical bonding that creates a chemical compound. When two or more elements bond and create a new substance, it is referred to as a chemical compound. With ionic bonding, atoms within the elements trade electrons so that each atom has a full outer shell. Ionic bonding occurs between metals and non-metals. With covalent bonding, a second type of bonding, atoms within elements share electrons. Covalent bonds occur between metals and metals and between non-metals and non-metals. Chemical compounds formed by ionic bonding are called ionic compounds, and chemical compounds formed by covalent bonding are called covalent compounds.
Elements & Atoms
An element is a primary component of matter. It contains only one type of atom and cannot be broken down into a simpler substance. Scientists have discovered 118 elements, which are listed in the periodic table.
An atom is the smallest unit of an element. Each atom has a specific number of protons in its nucleus, or center. An element's atomic number is the number of protons within the nucleus of its atoms. For example, oxygen's atomic number is eight, which means its atoms have eight protons.
An atom has the same number of protons and electrons, but its electrons orbit, or spin around, the atom's nucleus much the way planets orbit the sun. Electrons orbit in orbitals, which are commonly called shells. The first shell, the inner shell, can hold two electrons. The next shell can hold eight electrons. The first eighteen elements on the periodic table can hold eight electrons at most in the third, or outer, shell. (The elements after the first eighteen can hold more electrons in their third shell.)
How Ionic Bonding Occurs
Ionic bonding occurs between charged particles that are metals and non-metals. Metals most often have one, two, or three electrons in their outer shell while non-metals have five, six, or, seven electrons. An atom's outer shell is considered "full" if it has as many electrons as the shell can hold or if it has no electrons in this shell. If an atom has no electrons in its third shell, its second shell becomes its outer shell. If this shell contains the maximum number of electrons, the atom is stable. Atoms with an outer shell that is not full are unstable, so these atoms seek to either gain or get rid of some electrons. The electrons an atom must gain or lose to have a full outer shell are called valence electrons.
The chemical compound sodium chloride is commonly known as table salt. The formula for this compound is NaCl. Sodium (Na) has eleven electrons, so it has an atomic number of eleven. An atom of sodium has two electrons in its first shell, eight in its second shell, and one in its outer shell. At atom of chlorine (Cl) has two electrons in its first shell, eight in its second shell, and seven in its outer shell. When a sodium atom binds with a chlorine atom, the sodium atom gives away the electron in its outer shell. This means that its outer shell is empty and the atom is stable. The chlorine atom picks up this electron. Now the chlorine atom has eight electrons in its outer shell and is also stable.
Atoms with more electrons than protons have a negative charge, and atoms with more protons than electrons have a positive charge. Therefore, an atom that gains electrons has a negative charge and an atom that gives away electrons has a positive charge. An atom with a negative charge is called an anion; an atom with a positive charge is called a cation. In the case of sodium chloride, the sodium atoms have a positive charge and the chlorine atoms have a negative charge.
Composition of Ionic Bonds
The opposite charges attract one another and make an ionic bond very strong, stronger than a covalent bond. Chemical compounds created by ionic bonding are called ionic compounds.
The charges within ionic compounds must be neutral, not positive or negative. This means that the positive and negative charges within an ionic compound must cancel out each other. To do this, there must be an even number of anions and cations.
Ionic compounds have a very specific composition. They form a three-dimensional crystal lattice with alternating rows of positively and negatively charged atoms. Each negatively charged atom is surrounded by several positively charged atoms and vice versa.
Ionic compounds also have distinct characteristics. They are more likely to be solids than other compounds. The strong forces of attraction within them create a tight bond that is hard, rigid, and brittle like an egg shell. Because of their strong bonds of attraction, they also have a high melting point and boiling point. It takes a great deal of energy to melt or boil an ionic compound. Ionic compounds dissolve in water. Once dissolved, they can conduct electricity because the ionic bonds are broken and the atoms are separated and once again charged.
Bibliography
"Chemistry for Kids: Chemical Bonding."Ducksters, www.ducksters.com/science/chemistry/chemical‗bonding.php. Accessed 11 Oct. 2024.
"The Ionic Bond." Sparknotes, www.sparknotes.com/chemistry/bonding/ionic/section1/. Accessed 11 Oct. 2024.
"Which Elements Form Ionic Bonds?"The Chem Team, www.chemteam.info/Bonding/Ionic-Bond-Which-Elements.html. Accessed 11 Oct. 2024.